Low smoke halogen free flame retardant thermoplastic vulcanizate compositions containing zeolites

ABSTRACT

Halogen-free flame retardant compositions comprising thermoplastic vulcanizates, which exhibit desired flame retardance and low-smoke emission. These flame retardant compositions comprise a) one or more thermoplastic vulcanizates, and b) from at or about 18 to at or about 50 weight percent, the weight percentage being based on the total weight of the flame retardant composition, of a flame retardant mixture comprising: b1) at least one flame retardant comprising a phosphinate, diphosphinate and/or polymers thereof, b2) a phosphorous-containing amino composition, and b3) a zeolite.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional application No.61/448,319, filed Mar. 2, 2011.

FIELD OF THE INVENTION

The present invention relates to the field of low smoke halogen freeflame retardant compositions comprising thermoplastic vulcanizates.

BACKGROUND OF THE INVENTION

The design flexibility afforded by many thermoplastic resincompositions, their relative light weight and corrosion resistance makethem attractive materials for many uses, including the replacement ofmetal components in many applications including motor and recreationalvehicles, appliances, tools, electronics, furniture, and toys. However,in the construction, furniture, transport or electrical/electronicindustries, thermoplastic resin compositions are preferably made flameretardant to promote product safety, prevent the spread of fire andreduce destruction of products exposed to fire. The conventionalpractice of imparting flame retardance to thermoplastic resincompositions has been the addition of one or more flame retardants or aflame retardant mixture, which typically include a halogenated organiccompound such as brominated polystyrene as the flame retardant and anantimony compound as a synergist for the retardant.

However, halogenated flame retardants tend to decompose or degrade atthe processing temperatures of thermoplastic resins, which implicatespotential health and environmental effects due to the gases that arereleased. Consequently, there has been a trend away from usinghalogenated compounds or mixtures containing them to impart flameretardance.

Another conventional approach to impart flame retardance tothermoplastic resin compositions has been the addition of redphosphorus. Int'l. Pat. App. Pub. No. WO 92/20731 discloses acomposition comprising an elastomer, a flame retardant comprising redphosphorus and ammonium polyphosphate as a flame retardant synergist.Moreover, the use of fine red phosphorus powder homogeneously dispersedin the resin is known and practiced. In addition to the hazards of fireand explosion related to handling fine red phosphorus powders, the verycombustion of red phosphorus causes the emission of toxic fumes due tothe formation of phosphine.

To avert the hazards of using halogenated flame retardants and redphosphorus, phosphinate salts, that is, salts of phosphinic acids, alsoknown as phosphinates, have been substituted in thermoplastic resincompositions. DE Pat. Nos. 2,252,258 and 2,447,727 disclose phosphinatesused as flame retardants, U.S. Pat. No. 4,180,495 discloses the use ofpoly(metal phosphinate) salts in flame retardant polyesters andpolyamides. U.S. Pat. No. 6,255,371 discloses flame retardantcompositions comprising a) phosphinates, diphosphinates, or polymers ofthese and b) condensation products of melamine, reaction products ofmelamine with phosphoric acid, reaction products of condensationproducts of melamine with phosphoric acid and/or mixtures of these. U.S.Pat. No. 6,270,560 discloses salt mixtures made from aluminumphosphinates, aluminum hydroxide, aluminum phosphonates and/or aluminumphosphates suitable as flame retardants for polymeric moldingcompositions. U.S. Pat. Nos. 5,780,534 and 6,013,707 disclose flameretardant polyester compositions containing calcium or aluminum salts ofphosphinic acid or disphosphinic acid.

Thermoplastic vulcanizates (TPVs) combine many desirable characteristicsof crosslinked rubbers with some characteristics of thermoplasticelastomers. When the curable blend is melt extruded, the resultant TPVis processable in many ways like a thermoplastic elastomer, but retainsthe characteristics of a crosslinked rubber. U.S. Pat. App. Pub. No.2009/0176091 discloses a flame retardant composition comprising amelt-processable thermoplastic vulcanizate and at least one flameretardant comprising a phosphinate of the formula (I) and/or adiphosphinate of the formula (II) and/or polymers of these, which aredescribed in U.S. Pat. No. 6,255,371.

A disadvantage of using halogen-free, flame retardant compositionscomprising thermoplastic vulcanizates is that, upon exposure to flame,such compositions emit a high level of smoke, which can cause smokeinhalation hazards severe enough to require evacuation of the workplace.Therefore, a need remains for halogen-free, flame retardant compositionscomprising thermoplastic vulcanizates which exhibit the desired flameretardance as well as low smoke emission properties.

SUMMARY OF THE INVENTION

The present invention is directed to flame retardant polymercompositions comprising:

-   -   a) one or more thermoplastic vulcanizates; and    -   b) from at or about 18 to at or about 50 weight percent, based        on the total weight of the flame retardant polymer composition,        of a flame retardant mixture comprising:        -   b1) at least one flame retardant comprising a material            selected from the group consisting of phosphinates of the            formula (I); diphosphinates of the formula (II); polymers of            (I); polymers of (II); and mixtures of two or more thereof;

-   -   -   -   wherein R₁ and R₂ are independently selected from                hydrogen, linear or branched C₁-C₆ alkyl groups, and                aryl groups; R₃ is a linear or branched C₁-C₁₀-alkylene                group, a C₆-C₁₀-arylene group, or an -alkylarylene or                -arylalkylene group; M is selected from the group                consisting of calcium, magnesium, aluminum, zinc and                mixtures thereof; m is 2 to 3; n is 1 or 3; and x is 1                or 2;

        -   b2) a phosphorous-containing amino composition selected from            the group consisting of melamine phosphates, derivatives of            melamine phosphates and mixtures thereof; reaction products            of ammonia with phosphoric acid, polyphosphates of said            reaction products, and mixtures thereof; and

        -   b3) a zeolite

        -   wherein i) b1) is present in the flame retardant polymer            composition in an amount greater than or equal to 15 weight            percent based on the total weight of the flame retardant            polymer composition, ii) b2) is present in the flame            retardant mixture b) in an amount such that the amount of            b2) is less than the amount of b1), iii) b1) is present in            the flame retardant mixture b) in an amount from at or about            30 to at or about 85 weight percent, b2) is present in the            flame retardant mixture b) in an amount greater than 10 to            at or about 30 weight percent, and b3) is present in the            flame retardant mixture b) in an amount from at or about 4            to at or about 40 weight percent, provided that the sum b1)            b2) b3) is 100 weight percent.

In a preferred embodiment, the phosphorous-containing amino compositionb2) is melamine pyrophosphate or melamine polyphosphate, preferablymelamine pyrophosphate and in an even more preferred embodiment, theamount of melamine pyrophosphate is greater than 2 weight percent basedon the total weight of the flame retardant polymer composition.

In an even more preferred embodiment, the flame retardant polymercomposition comprises from at or about 18 to at or about 50 weightpercent, preferably from at or about 20 to at or about 40 weight percentof the flame retardant mixture described above wherein b1) is present inthe flame retardant polymer composition in an amount of from at or about15 to at or about 25 weight percent, b2) is present in the flameretardant polymer composition in an amount from at or about 5 to at orabout 25 weight percent and b3) is present in the flame retardantpolymer composition in an amount from at or about 2 to at or about 20weight percent, the percentage of flame retardant mixture in the polymercomposition being based on the total weight of the flame retardantpolymer composition.

Also described herein are molded, extruded, or shaped articlescomprising the flame retardant composition described above. Furtherdescribed herein are wires or cables comprising a coating made of theflame retardant compositions described herein.

In addition, the invention is directed to a flame retardant compositioncomprising

-   -   A) at least one flame retardant comprising a material selected        from the group consisting of phosphinates of the formula (I);        diphosphinates of the formula (II); polymers of (I); polymers of        (II); and mixtures of two or more thereof;

-   -   -   wherein R₁ and R₂ are independently selected from hydrogen,            linear or branched C₁-C₆ alkyl groups, and aryl groups; R₃            is a linear or branched C₁-C₁₀-alkylene group, a            C₆-C₁₀-arylene group, or an -alkylarylene or -arylalkylene            group; M is selected from the group consisting of calcium,            magnesium, aluminum, zinc and mixtures thereof; m is 2 to 3;            n is 1 or 3; and x is 1 or 2;

    -   B) a phosphorous-containing amino composition selected from the        group consisting of melamine phosphates, derivatives of melamine        phosphates and mixtures thereof; and

    -   C) a zeolite

    -   wherein A) is present in the flame retardant composition in an        amount from at or about 30 to at or about 85 weight percent, B)        is present in the flame retardant composition in an amount        greater than 10 to at or about 30 weight percent, and C) is        present in the flame retardant composition in an amount from at        or about 4 to at or about 40 weight percent, provided that the        sum A)+B)+C) is 100 weight percent.

Also described herein are uses of flame retardant compositions describedherein for imparting flame retardance and low smoke emission tocompositions comprising thermoplastic vulcanizates.

DETAILED DESCRIPTION OF THE INVENTION

The following definitions are to be used to interpret the meaning of theterms discussed in the description and recited in the claims.

As used herein, the article “a” indicates one as well as more than oneand does not necessarily limit its referent noun to the singular.

As used herein, the terms “about” and “at or about” mean that the amountor value in question may be the value designated or some other valuethat is approximately or about the same. The phrase is intended toconvey that similar values promote equivalent results or effectsaccording to the invention.

As used herein, the term “thermoplastic vulcanizates” (TPV's) refers toblends consisting of a continuous thermoplastic phase with a phase ofvulcanized elastomer dispersed therein.

As used herein, the terms “vulcanizate” and “vulcanizate rubber” aregeneric and refer to cured or partially cured, crosslinked orcrosslinkable rubber as well as to curable precursors of crosslinkedrubber and include elastomers, gum rubbers and so-called softvulcanizates.

As used herein, the term “(meth)acrylic acid” refers to methacrylic acidand/or acrylic acid; the term “(meth)acrylate” refers to methacrylateand/or acrylate and the term “poly(meth)acrylate refers to polymersderived from the polymerization of methacrylate and/or acrylatemonomers.

As used herein, the term “organic multiolefinic co-agent” refers toorganic co-agents that contain two or more unsaturated double bonds.

The one or more thermoplastic vulcanizates suitable for use in the flameretardant compositions described herein are preferably present in thepolymer compositions of the invention in an amount from at or about 50to at or about 80 weight percent, the weight percentage being based onthe total weight of the flame retardant polymer composition, i.e. thesum of the thermoplastic vulcanizate component, flame retardant mixturecomponent (i.e. the component comprising a flame retardant comprising amaterial selected from the group of phosphinates of formula (I),diphosphinates of formula (II), polymers thereof, and mixtures thereof),phosphorous-containing amino composition component, zeolite componentand any optional components. This may also be expressed as the sum ofa)+b1) b2) b3) plus any optional components.

Thermoplastic vulcanizates (TPVs) combine many desirable characteristicsof crosslinked rubbers with some characteristics that are typical ofthermoplastic elastomers, for example thermoplastic processability.Preferably, the one or more thermoplastic vulcanizates present in theflame retardant compositions described herein include polyester basedthermoplastic vulcanizates, polyolefin based thermoplastic vulcanizates(TPO-V), nitrile rubber-nylon thermoplastic vulcanizates, thermoplasticsilicone vulcanizates (TPSi-V), acrylate based thermoplasticvulcanizates (TPA-V), nitrile rubber-polypropylene thermoplasticvulcanizates, and butyl rubber polypropylene thermoplastic vulcanizates.There are several commercially available TPVs. These include Santoprene®thermoplastic vulcanizates and Sarlink® plastic resins, which comprisecrosslinked ethylene-propylene-diene copolymers (EPDMs) in apolypropylene matrix, and which are available from Advanced ElastomerSystems and DSM; Nex Trile™ NBR/PP based TPV, which comprisescrosslinked nitrile rubber and polypropylene, and which is availablefrom Thermoplastic Rubber Systems; Zeotherm® TPV, which comprises acrosslinked acrylate elastomer and polyimide and which is available fromZeon Chemicals; and DuPont™ ETPV engineering thermoplastic vulcanizates,described in Int'l. Pat. App. Pub. No. WO 2004/029155 as thermoplasticblends comprising from 15 to 60 weight percent of polyalkylene phthalatepolyester polymer or copolymer and from 40 to 85 weight percent of acrosslinkable poly(meth)acrylate or polyethylene/(meth)acrylate rubberdispersed phase, wherein the rubber is dynamically crosslinked with aperoxide free radical initiator and an organic multiolefinic co-agent,and which are available from E.I. du Pont de Nemours and Company,Wilmington, Del.

Preferably, the one or more thermoplastic vulcanizates present in theflame retardant compositions described herein are polyester basedthermoplastic vulcanizates, i.e., they comprise a continuousthermoplastic phase that is a polyester resin and a crosslinked orcrosslinkable polyethylene/(meth)acrylate rubber phase.

Examples of polyester resins include thermoplastic polyesters,copolyester elastomers and copolyetherester elastomers. U.S. Pat. No.7,074,857, U.S. Pat. App. Pub. No. 20051084694 and Int'l. Pat. App. Pub.No. WO 2004/029155 describe thermoplastic vulcanizates comprising acontinuous thermoplastic phase that is a polyester resin, all three ofwhich are hereby incorporated herein by reference. Int'l. Pat. App. Pub.No. WO 2004/029155 describes a curable thermoplastic blend comprising apolyalkylene phthalate polyester polymer or copolymer and acrosslinkable poly(meth)acrylate or polyethylene/(meth)acrylatevulcanizate rubber in combination with an effective amount of peroxidefree radical initiator and an organic multiolefinic co-agent tocrosslink the rubber during extrusion or injection molding of thethermoplastic elastomeric blend composition.

When one or more of such thermoplastic vulcanizates are present in theflame retardant compositions described herein each will preferablycomprise i) from at or about 15 to at or about 75 weight percent,preferably from at or about 15 to at or about 60 weight percent, of atleast one thermoplastic polyester continuous phase, and ii) from at orabout 25 to at or about 85 weight percent, preferably from at or about40 to at or about 85 weight percent, of at least one poly(meth)acrylateor polyethylene/(meth)acrylate rubber that forms a dispersed phase,wherein the rubber is dynamically crosslinked after dispersion in thecontinuous phase with at least one peroxide free radical initiator andat least one organic multiolefinic co-agent, the weight percentages foreach thermoplastic vulcanizate being based on the total weight of therespective components (i.e. components i+ii) of the copolyetherestervulcanizate. Thus, the weight percentage of the thermoplastic polyesterin a thermoplastic vulcanizate is based on the combined weight of thethermoplastic polyester and the ethylene/(meth)acrylate rubber in thethermoplastic vulcanizate.

(Meth)acrylate rubbers that form the crosslinkable component ofpreferred TPVs useful in the compositions of the present invention maybe prepared by copolymerizing one or more (meth)acrylate monomers withone or more olefins. A preferred olefin is ethylene. As used herein, theterm “crosslinked acrylate rubber” refers to component (ii). Examples ofpreferable (meth)acrylate rubbers include poly(alkyl (meth)acrylate)rubbers, ethylene/alkyl (meth)acrylate copolymer rubber andpoly(perfluoroalkyl (meth)acrylate) rubbers. More preferable areethylene/alkyl (meth)acrylate copolymer rubbers where the alkyl grouphas from 1 to 4 carbons is used. Preferred ethylene/alkyl (meth)acrylatecopolymers are those derived from less than about 80 weight percentethylene and more than about 20 weight percent alkyl (meth)acrylate, theweight percentages being based on the total weight of the ethylenecopolymer.

The (meth)acrylate rubbers may optionally comprise additionalcopolymerized monomer units, i.e. repeat units, derived from one or morefunctionalized comonomers, such as (meth)acrylate glycidyl esters (suchas glycidyl methacrylate), maleic add, or other comonomers having one ormore reactive groups such as add, hydroxyl, epoxy, isocyanates, amine,oxazoline, chloroacetate, or diene groups. The (meth)acrylate rubbersmay also be prepared from more than two (meth)acrylate monomers.Examples are (meth)acrylate rubbers made by polymerizing ethylene,methyl acrylate, and a second acrylate (such as butyl acrylate). Thus,the (meth)acrylate rubbers may be ethylene dipolymers, terpolymers orhigher order copolymers.

Suitable free radical initiators used to crosslink the (meth)acrylatesinclude but are not limited to2,5-dimethyl-2,5-di-(t-butylperoxy)hexyne-3; t-butyl peroxybenzoate;2,5-dimethyl-2,5-di-(t-butylperoxy)hexane; dicumyl peroxide;α,α-bis(t-butylperoxy)-2,5-dimethylhexane; and the like. Suitableorganic multiolefinic co-agents for use in the curative system for thepreferred polyester TPVs include, but are not limited to, diethyleneglycol diacrylate; diethylene glycol dimethacrylate, N,N′-m-phenylenedimaleimide; triallylisocyanurate; trimethylolpropane trimethacrylate;tetraallyloxyethane; triallyl cyanurate; tetramethylene diacrylate;polyethylene glycol dimethacrylate; and the like.

Preferred thermoplastic polyesters that form the continuous phase of thethermoplastic component useful in the compositions of the invention aretypically derived from one or more dicarboxylic acids (where herein theterm “dicarboxylic acid” also refers to dicarboxylic acid derivativessuch as esters) and one or more diols. In preferred polyesters thedicarboxylic acids comprise one or more of terephthalic acid,isophthalic acid, and 2,6-naphthalene dicarboxylic acid, and the diolcomponent comprises one or more of HO(CH₂)_(n)OH (I);1,4-cyclohexanedimethanol; HO(CH₂CH₂O)_(m)CH₂CH₂OH(H); andHO(CH₂CH₂CH₂CH₂O)_(z)CH₂CH₂CH₂CH₂OH (III), wherein n is an integer of 2to 10, m on average is 1 to 4, and z is on average about 7 to about 40.The diol components (II) and (III) may be a mixture of compounds inwhich m and z, respectively, may vary. Because m and z are averages,they need not be integers. Other dicarboxylic acids that may be used toform the thermoplastic polyester include sebacic and adipic acids.Hydroxycarboxylic acids such as hydroxybenzoic acid may be used ascomonomners. Specific preferred polyesters include poly(ethyleneterephthalate) (PET), poly(trimethylene terephthalate) (PTT),poly(1,4-butylene terephthalate) (PBT), poly(ethylene 2,6-naphthoate),and poly(1,4-cyclohexyldimethylene terephthalate) (PCT).

Alternatively, the thermoplastic polyester continuous phase (i)comprises at least one copolyester elastomer, copolyetherester elastomerand/or mixtures thereof, copolyetherester elastomers being preferred.

Copolyetherester elastomers are especially suitable for use in thethermoplastic vulcanizates that form the first component of the flameretardant compositions of the invention. These polymers constitute agroup of thermoplastic elastomers that have a multiplicity of recurringlong-chain ester units and short-chain ester units joined head-to-tailthrough ester linkages, said long-chain ester units being represented byformula (A):

and said short-chain ester units being represented by formula (B):

whereinG is a divalent radical remaining after the removal of terminal hydroxylgroups from poly(alkylene oxide)glycols having a number averagemolecular weight of between about 400 and about 6000, or preferablybetween about 400 and about 3000;R is a divalent radical remaining after removal of carboxyl groups froma dicarboxylic acid having a molecular weight of less than about 300;D is a divalent radical remaining after removal of hydroxyl groups froma diol having a molecular weight less than about 250.

As used herein, the term “long-chain ester units” as applied to units ina polymer chain refers to the reaction product of a long-chain glycolwith a dicarboxylic acid. Suitable long-chain glycols are poly(alkyleneoxide) glycols having terminal (or as nearly terminal as possible)hydroxy groups and having a number average molecular weight of fromabout 400 to about 6000, and preferably from about 600 to about 3000.Preferred poly(alkylene oxide) glycols include poly(tetramethyleneoxide) glycol, poly(trimethylene oxide) glycol, poly(propylene oxide)glycol, polyethylene oxide) glycol, copolymer glycols of these alkyleneoxides, and block copolymers such as ethylene oxide-cappedpoly(propylene oxide) glycol. Mixtures of two or more of these glycolscan be used.

As used herein, the term “short-chain ester units” as applied to unitsin a polymer chain of the copolyetheresters refers to low molecularweight compounds or polymer chain units having molecular weights lessthan about 550. They are prepared by reacting a low molecular weightdiol or a mixture of diols (molecular weight below about 250) with adicarboxylic acid to form ester units represented by Formula (B) above.

Included among the low molecular weight diols which react to formshort-chain ester units suitable for use for preparing copolyetherestersare acyclic, alicyclic and aromatic dihydroxy compounds. Preferredcompounds are diols with about 2-15 carbon atoms such as ethylene,propylene, isobutylene, tetramethylene, 1,4-pentamethylene,2,2-dimethyltrimethylene, hexamethylene and decamethylene glycols,dihydroxycyclohexane, cyclohexane dimethanol, resorcinol, hydroquinone,1,5-dihydroxynaphthalene, etc. Especially preferred diols are aliphaticdiols containing 2-8 carbon atoms, and a more preferred diol is1,4-butanediol. Included among the bisphenols which can be used arebis(p-hydroxy)diphenyl, bis(p-hydroxyphenyl)methane, andbis(p-hydroxyphenyl)propane. Equivalent ester-forming derivatives ofdiols are also useful (e.g., ethylene oxide or ethylene carbonate can beused in place of ethylene glycol or resorcinol diacetate can be used inplace of resorcinol).

As used herein, the term “diols” includes equivalent ester-formingderivatives such as those mentioned. However, any molecular weightrequirements refer to the corresponding diols, not their derivatives.

Dicarboxylic acids that can react with the foregoing long-chain glycolsand low molecular weight diols to produce the copolyetheresters arealiphatic, cycloaliphatic or aromatic dicarboxylic acids of a lowmolecular weight, i.e., having a molecular weight of less than about300. The term “dicarboxylic acids” as used herein includes functionalequivalents of dicarboxylic acids that have two carboxyl functionalgroups that perform substantially like dicarboxylic acids in reactionwith glycols and diols in forming copolyetherester polymers. Theseequivalents include esters and ester-forming derivatives such as acidhalides and anhydrides. The molecular weight requirement pertains to theacid and not to its equivalent ester or ester-forming derivative.

Thus, an ester of a dicarboxylic acid having a molecular weight greaterthan 300 or a functional equivalent of a dicarboxylic acid having amolecular weight greater than 300 are included provided thecorresponding acid has a molecular weight below about 300. Thedicarboxylic acids can contain any substituent groups or combinationsthat do not substantially interfere with the copolyetherester polymerformation and use of the polymer in the flame retardant compositions ofthe invention.

As used herein, the term “aliphatic dicarboxylic acids” refers tocarboxylic acids having two carboxyl groups each attached to a saturatedcarbon atom. If the carbon atom to which the carboxyl group is attachedis saturated and is in a ring, the acid is cycloaliphatic. Aliphatic orcycloaliphatic acids having conjugated unsaturation often cannot be usedbecause of homopolymerization. However, some unsaturated acids, such asmaleic acid, can be used.

As used herein, the term “aromatic dicarboxylic acids” refers todicarboxylic acids having two carboxyl groups each attached to a carbonatom in a carbocyclic aromatic ring structure. It is not necessary thatboth functional carboxyl groups be attached to the same aromatic ringand where more than one ring is present, they can be joined by aliphaticor aromatic divalent radicals or divalent radicals such as —O— or —SO₂—.Representative useful aliphatic and cycloaliphatic acids that can beused include sebacic acid; 1,3-cyclohexane dicarboxylic acid;1,4-cyclohexane dicarboxylic acid; adipic acid; glutaric acid;4-cyclohexane-1,2-dicarboxylic acid; 2-ethylsuberic acid;cyclopentanedicarboxylic acid; decahydro-1,5-naphthylene dicarboxylicacid; 4,4′-bicyclohexyl dicarboxylic acid; decahydro-2,6-naphthylenedicarboxylic acid; 4,4′-methylenebis(cyclohexyl) carboxylic acid; and3,4-furan dicarboxylic acid. Preferred acids arecyclohexane-dicarboxylic acids and adipic acid.

Representative aromatic dicarboxylic acids include phthalic,terephthalic and isophthalic acids; bibenzoic acid; substituteddicarboxy compounds with two benzene nuclei such asbis(p-carboxyphenyl)methane; p-oxy-1,5-naphthalene dicarboxylic acid;2,6-naphthalene dicarboxylic acid; 2,7-naphthalene dicarboxylic acid;4,4′-sulfonyl dibenzoic acid and C₁-C₁₂ alkyl and ring substitutionderivatives thereof, such as halo, alkoxy, and aryl derivatives. Hydroxyacids such as p-(beta-hydroxyethoxy)benzoic acid can also be usedprovided an aromatic dicarboxylic acid is also used.

Aromatic dicarboxylic acids are a preferred class for preparing thecopolyetherester elastomers useful in the compositions of thisinvention. Among the aromatic acids, those with 8-16 carbon atoms arepreferred, particularly terephthalic acid alone or with a mixture ofphthalic and/or isophthalic acids.

The copolyetherester elastomers preferably comprise from at or about 15to at or about 99 weight percent short-chain ester units correspondingto Formula (B) above, the remainder being long-chain ester unitscorresponding to Formula (A) above. More preferably, thecopolyetherester elastomers comprise from at or about 20 to at or about95 weight percent, and even more preferably from at or about 50 to at orabout 90 weight percent short-chain ester units, where the remainder islong-chain ester units. More preferably, at least about 70% of thegroups represented by R in Formulae (A) and (B) above are 1,4-phenyleneradicals and at least about 70% of the groups represented by D inFormula (B) above are 1,4-butylene radicals and the sum of thepercentages of R groups which are not 1,4-phenylene radicals and Cgroups that are not 1,4-butylene radicals does not exceed 30%. If asecond dicarboxylic acid is used to prepare the copolyetherester,isophthalic acid is preferred and if a second low molecular weight diolis used, ethylene glycol, 1,3-propanediol, cyclohexanedimethanol, orhexamethylene glycol are preferred.

A blend or mixture of two or more copolyetherester elastomers can alsobe used. The copolyetherester elastomers utilized in the blend need noton an individual basis come within the values disclosed hereinbefore forthe elastomers. However, the blend of two or more copolyetheresterelastomers must conform to the values described herein for thecopolyetheresters on a weighted average basis. For example, in a mixturethat contains equal amounts of two copolyetherester elastomers, onecopolyetherester elastomer can contain 60 weight percent short-chainester units and the other resin can contain 30 weight percentshort-chain ester units for a weighted average of 45 weight percentshort-chain ester units.

Preferred copolyetherester elastomers include, but are not limited to,copolyetherester elastomers prepared from monomers comprising (1)poly(tetramethylene oxide) glycol; (2) a dicarboxylic acid selected fromisophthalic acid, terephthalic acid and mixtures thereof; and (3) a diolselected from 1,4-butanediol, 1,3-propanediol and mixtures thereof, orfrom monomers comprising (1) poly(trimethylene oxide) glycol; (2) adicarboxylic acid selected from isophthalic acid, terephthalic acid andmixtures thereof; and (3) a diol selected from 1,4-butanediol,1,3-propanediol and mixtures thereof, or from monomers comprising (1)ethylene oxide-capped polypropylene oxide) glycol; (2) dicarboxylic acidselected from isophthalic acid, terephthalic acid and mixtures thereof;and (3) a diol selected from 1,4-butanediol, 1,3-propanediol andmixtures thereof.

Preferably, the copolyetherester elastomers described herein areprepared from esters or mixtures of esters of terephthalic acid and/orisophthalic acid, 1,4-butanediol and poly(tetramethylene ether)glycol orpoly(trimethylene ether) glycol or ethylene oxide-capped polypropyleneoxide glycol, or are prepared from esters of terephthalic acid, e.g.dimethylterephthalate, 1,4-butanediol and poly(ethylene oxide)glycol.More preferably, the copolyetheresters are prepared from esters ofterephthalic acid; e.g. dimethylterephthalate, 1,4-butanediol andpoly(tetramethylene ether)glycol.

Thermoplastic vulcanizates wherein the continuous thermoplastic phasecomprises a copolyetherester elastomer described herein may be preparedusing methods described in Int'l. Pat. App. Pub. No. WO 2004/029155.Examples of suitable copolyetherester elastomers useful as thecontinuous phase of thermoplastic vulcanizates are commerciallyavailable under the trademark Hytrel® polyetherester from E. I. du Pontde Nemours and Company, Wilmington, Del.

The actual mixing of components and subsequent dynamic crosslinkingprocess used to prepare the thermoplastic vulcanizates may be performedeither in a batch mode or a continuous mode using conventional meltblending equipment. An exemplary method of preparation of athermoplastic vulcanizate comprises:

(a) adding and admixing a crosslinkable poly(meth)acrylate orpolyethylene/(meth)acrylate rubber, at least one peroxide free radicalinitiator and at least one organic multiolefinic co-agent in a meltextruder or melt blender at a temperature insufficient to promotesignificant crosslinking;(b) adding a copolyetherester elastomer to the melt extruder or meltblender and admixing the copolyetherester resin with the crosslinkablepoly(meth)acrylate or polyethylene/(meth)acrylate vulcanizate rubberprior to crosslinking;(c) further mixing the crosslinkable poly(meth)acrylate orpolyethylene/(meth)acrylate vulcanizate rubber with the at least oneperoxide free radical initiator and the at least one organicmultiolefinic co-agent with the copolyetherester resin at conditions andtemperature sufficient to crosslink the crosslinkable poly(meth)acrylateor polyethylene/(meth)acrylate vulcanizate rubber; and(d) recovering the copolyetherester vulcanizate comprising thecopolyetherester elastomer as a continuous phase and of thepoly(meth)acrylate or polyethylene/(meth)acrylate vulcanizate rubbercrosslinked with the at least one peroxide free radical initiator andthe at least one organic multiolefinic co-agent as a disperse phase.

Similar methods may be used to prepare compositions of the inventionwherein the thermoplastic vulcanizate is selected from thermoplasticvulcanizates other than those that contain polyesters as a continuousphase.

A particularly suitable copolyetherester vulcanizate for use in theflame retardant compositions disclosed herein is DuPont™ ETPVengineering thermoplastic vulcanizate, commercially available from E. I.du Pont de Nemours and Company, Wilmington, Del. This material canreplace crosslinked high performance rubber in these flame retardantcompositions because it has low hardness in the Shore A range, can beprocessed by standard thermoplastic processing techniques to result insignificant cost savings, and has excellent oil and heat resistance aswell as recyclability.

Flame retardance in the flame retardant thermoplastic vulcanizatecompositions described herein is imparted by flame retardant mixturesalso referred to herein as flame retardant compositions. These flameretardant mixtures b) comprise a flame retardant b1) which is aphosphinate of the formula (I) (i.e. a monophosphinate) and/or adiphosphinate of the formula (II) and/or polymers of (I) and/or (II),

wherein R₁ and R₂ are identical or different and are hydrogen, linear orbranched C₁-C₆ alkyl groups, and/or aryl groups; R₃ is a linear orbranched C₁-C₁₀-alkylene group, a C₆-C₁₀-arylene group, an -alkylaryleneor -arylalkylene group; M is calcium, magnesium, aluminum, and/or zinc;m is 2 to 3; n is 1 or 3; and x is 1 ort.

R₁ and R₂ may be identical or different and are preferably hydrogen,methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-pentyl and/orphenyl. R₃ is preferably methylene, ethylene, n-propylene, isopropylene,n-butylene, tert-butylene, n-pentylene, n-octylene, n-dodecylene, orphenylene or naphthylene, or methylphenylene, ethylphenylene,tert-butylphenylene, methylnaphthylene, ethylnaphthylene ortert-butylnaphthylene, or phenylmethylene, phenylethylene,phenylpropylene or phenylbutylene. M is preferably aluminum or zinc.

By polymers of the compounds of formulas (I) and (II) is meant speciescontaining oligomers or condensation products of the phosphinate anddiphosphinate anion moieties.

Preferred phosphinates are metal salts of organic phosphinates, such asmetal salts of methylethylphosphinates and diethylphosphinates. Morepreferred are aluminum methylethylphosphinate, aluminumdiethylphosphinate, zinc methylethylphosphinate, and zincdiethylphosphinate. More preferably, the flame retardant is aluminumphosphinate, magnesium phosphinate, calcium phosphinates and/or zincphosphinate and still more preferably, the flame retardant is aluminumphosphinate, aluminum diethyl phosphinate and/or zinc diethylphosphinate.

Although the flame retardant composition may contain both amonophosphinate and a diphosphinate or a diphosphinate alone, preferredcompositions contain monophosphinates due to cost and availability.

The flame retardant b1) is usually in the form of particles which mayhave any particle size distribution, as commonly understood and used bythose having skill in the field, but preferably the phosphinate and/ordiphosphinates that comprise component b1) have particle sizes (D90value) of less than or equal to 100 microns and more preferably lessthan or equal to 20 microns. The D90 value corresponds to a particlesize below which 90 weight percent of the particles lie, wherein theparticle size distribution is measured by the technique of laserdiffraction from a suspension of particles in a solvent using a particlesize analyzer, Mastersizer 2000 from Malvern. This test method meets therequirements set forth in ISO 13320.

Preferably, the flame retardant mixtures b) comprise a flame retardantb1) in an amount from at or about 30 to at or about 85 weight percent,the weight percentage being based on the total weight of the flameretardant mixture, i.e. the sum of components b1) b2) b3).

The flame retardant mixtures b) described herein comprise aphosphorous-containing amino composition, b2), that is a melaminephosphate, a derivative of a melamine phosphate or mixtures thereof, areaction product of ammonia with phosphoric acid or a polyphosphatethereof, for example melamine pyrophosphate or ammonium polyphosphate ormixtures thereof, in an amount such that the amount of b2) is lower thanthe amount of b1). Preferably the amount of b2) is greater than 10 to ator about 30 weight percent, the weight percentage being based on thetotal weight of the flame retardant mixture, i.e. the sum of componentsb1)+b2)+b3). Suitable phosphorous-containing amino compositions that arereaction products of ammonia with phosphoric acid or a polyphosphatederivative thereof include ammonium hydrogenphosphate, ammoniumdihydrogenphosphate and ammonium polyphosphate. More preferably, thephosphorous-containing amino compositions comprises melaminepyrophosphate or ammonium polyphosphate. Suitable phosphorous-containingamino compositions that are melamine phosphates include melamineorthophosphate (C₃H₆N₆H₃O₄P), dimelamine orthophosphate (C₃H₆N₆H₃O₄P)₂,melamine polyphosphate, dimelamine pyrophosphate, and melaminepyrophosphate. Derivatives of melamine phosphates include, for example,melem polyphosphate, melam polyphosphate and melamine borophosphates.

The material known as melamine pyrophosphate is a compound defined bythe nominal formula (C₃H₆N₆)₂H₄P₂O₇. Commercially available grades ofmelamine pyrophosphate may have substantial impurities in terms ofhaving a different ratio of phosphorous to nitrogen and/or containingother phosphorous containing anions. See U.S. Pat. No. 5,814,690.Nevertheless, any compound having the nominal melamine pyrophosphateformula above or sold commercially as melamine pyrophosphate is suitablefor use in the flame retardant compositions of the invention and fallswithin the scope of the recited invention.

The phosphorous-containing amino composition may also comprise coatedparticles, for example particles that have a core comprising melaminepyrophosphate and a coating comprising an organosilane, ester, polyol,dianhydride; dicarboxylic acid, melamine formaldehyde, or mixturesthereof. Such coated compositions are disclosed in U.S. Pat. No.6,015,510, the teaching of which is incorporated herein by reference. Anexample of a suitable coated melamine pyrophosphate is a melaminepyrophosphate coated with 0.6±0.1 wt. % Silquest® A-1100 silane.Alternatively, the coating agent may be added to thephosphorous-containing composition in a separate step prior to blendingwith one or more components of the composition of the invention or in astep wherein all components are mixed together. In such cases, theamount of coating agent will generally be in the range of from about 0.1to about 6 wt. %, based on the weight of the coatedphosphorous-containing composition.

The flame retardant mixture b) described herein also comprises from ator about 4 to at or about 40 weight percent of a zeolite b3), the weightpercentage being based on the total weight of the flame retardantmixture, i.e. the sum of components b1) b2) b3). Zeolites are hydroustectosilicate minerals characterized by a three-dimensionalaluminosilicate tetrahedral framework. The framework contains channelsand interconnected voids occupied by ion-exchangeable cations andloosely held water molecules permitting reversible dehydration.Preferred zeolites are represented by the general formula (III):

M_(2/n)O.Al₂O₃ .xSiO₂ .yH₂O  (III)

whereinM is a metal selected from alkali and alkaline earth metals, V, Mo, Mn,Fe, Co, Ni, Cu, Zn, Sb, Bi and mixtures thereof;n is the cation valence;x is from 0.1 and 20; andy is the number of moles of water of crystallization and has a value of0 to 20.

The zeolite b3) component may be naturally occurring or syntheticallyprepared. Examples of naturally occurring zeolites include analcite,analcime, cancrinite, chabazite, clinoptilolite, erionite, faujacite,heulandite, mordenite, natrolite, nosean, phillipsite and stilbite.Particularly suitable is a zeolite Y type.

It is generally preferred that zeolites are used in the form having anequilibrium moisture content, which is generally around 20-30 wt.% basedon the weight of the zeolite. Oven-drying may alter the pore structureof the zeolite, which is undesirable.

The flame retardant composition comprising the three components b1), b2)and b3) is itself a novel composition that may be used as an intumescentadditive in a variety of polymeric compositions wherein flame retardanceand smoke suppression is desired. Intumescence refers to a specificchemical reaction described as the formation, during combustion, of afoaming char instead of combustible gases. The charred layer serves as aphysical barrier, which slows down heat and mass transfer between thegas and the condensed phases. The composition may be used to impartflame retardancy and smoke suppression properties to a wide range ofpolymers, for example thermoplastics, elastomers and thermoplasticelastomers, including thermoplastic vulcanizates, copolyesterthermoplastic elastomers, thermoplastic polyamide copolymers,thermoplastic polyolefinic elastomers, styrenic thermoplasticelastomers, thermoplastic polyurethanes, copolyetherester elastomers,copolyesterester elastomers, polychloroprene, EPDM rubber,fluoroelastomers and ethylene acrylic elastomers.

The phosphorus-containing amino composition b2) in the flame retardantmixture described herein is preferably used in combination with otheringredients to form an intumescent system, i.e. thephosphorus-containing amino composition b2) is comprised in theintumescent system. The intumescent system comprises at least threecomponents; b2) as an acid source; a carbonific agent; and a spumificagent.

The acid source, the carbonific agent and the spumific agent may, incertain instances, be the same chemical compound. In such instances, thecompound will function as one or more of acid source, carbonific agentand spumific agent. For example, melamine polyphosphate can act as anacid source and a blowing agent. When an intumescent system comprisingthe phosphorus-containing amino composition b2) described herein is usedin the flame retardant mixtures described herein, the intumescent systemis generally present in the flame retardant mixture in an amount from ator about 15 to at or about 70 weight percent, preferably from at orabout 15 to at or about 65 weight percent, more preferably from at orabout 15 to at or about 60 weight percent of the flame retardantmixture, the weight percent being based on the total weight of the flameretardant mixture, i.e. the sum of a) component b1), plus theintumescent system, plus the zeolite. component b3) and wherein theintumescent system is the sum of the phosphorous-containing aminocomponent b2), the carbonific agent and the spumific agent.

The acid source b2) is a material that yields acidic species, forexample, upon heat exposure and acts as a catalyst. The acid source b2)in the intumescent system is the same as described in the precedingparagraphs above for the phosphorous-containing amino composition b2).With the aim of increasing thermal stability, improving water resistanceand improving dispersibility within the thermoplastic resin, the acidsource b2) may be coated, as described above for b2).

The carbonific agent in the intumescent system is also known as a carbonsource, char-promoting agent, char-forming agent or carbonizationcompound. The carbonific agent is an organic compound which will reactwith the liberated acidic species to yield a carbon char. The carbonificagent is preferably selected from the group consisting of polyhydricalcohols, saccharides, alkylol melamines, polyol(alkyl carbonates)phenol-formaldehyde resins, char-forming polymers, and mixtures ofthese. Examples of polyhydric alcohols include without limitationpentaerythritol, dipentaerythritol, tripentaerythritol andpolycondensates of pentaerythritol. Examples of saccharides includewithout limitation starches and their derivatives, dextrins,cyclodextrins, D-mannose, glucose, galactose, sucrose, fructose, xylose,arabinose, D-mannitol, D-sorbitol, D- or arabitol, xylitol, inositol,adonitol, dulcitol, iditol, talitol, allitol, altritol, guilitol,erythritol and threitol. Examples of char-forming polymers includewithout limitation polyamides, thermoplastic polyurethanes andpolycarbonates.

The spumific agent in the intumescent system is also known as a blowingagent or expanding agent and is a compound that generates non-flammablegases, such as carbon dioxide (CO₂), water, nitrogen (N₂) and ammonia,each of which causes the char to swell. The spumific agent is preferablyselected from amines, amides, ureas, guanidines, guanamines, triazines,melamines, amino acids, and salts of these. Examples of salts of amines,amides, ureas, guanidines, guanamines, triazines, melamines, and aminoacids include phosphates, phosphonates, phosphinates, borates,cyanurates and sulfates. Examples of amines and salts of these includewithout limitation ammonium phosphates, ammonium pyrophosphates,ammonium polyphosphates, ethylenediamine phosphates, ammonium cyanuratesand ammonium borates. Examples of melamine salts include withoutlimitation melamine phosphates (e.g. melamine orthophosphate, melaminediphosphate, melamine polyphosphate), melamine cyanurates, melamineborates, melamine borophosphates, melamine silicates, melamine1,2-phthalates, melamine 1,3-phthalates, melamine 1,4-phthalates,melamine guanidates and melamine oxalates.

The flame retardant polymer compositions described herein may furthercomprise additives that include, but are not limited to, one or more ofthe following components as well as combinations of these: metaldeactivators, such as hydrazine and hydrazide; heat stabilizers;antioxidants; modifiers; colorants, lubricants, fillers and reinforcingagents, impact modifiers, flow enhancing additives, antistatic agents,crystallization promoting agents, conductive additives, viscositymodifiers, nucleating agents, plasticizers, mold release agents, scratchand mar modifiers, drip suppressants, adhesion modifiers and otherprocessing aids known in the polymer compounding art. When used,additional additives are preferably present in amounts of about 0.1 toabout 20 weight percent, based on the total weight of the flameretardant polymer composition. In a preferred embodiment, the additivecomprises a high molecular weight polysiloxane. The use of a highmolecular weight polysiloxane as an additive in the flame retardantcompositions described herein improves the extrudability and theabrasion resistance of the compositions. When used, high molecularweight polysiloxanes are preferably present in amounts of about 0.05 toabout 175 weight percent, based on the total weight of the flameretardant polymer composition.

The flame retardant polymer compositions described herein may furthercomprise one or more amorphous polymers, such as polycarbonates,poly(methyl (meth)acrylate)s, and/or polyarylates. When present, the oneor more amorphous polymers preferably comprise about 1 to about 30weight percent, or more preferably about 10 to about 20 weight percentof the total flame retardant polymer composition. Such flame retardantpolymer compositions are particularly suited for use in wire and cablecoating applications and preferably such compositions also comprise oneor more metal deactivators, heat stabilizers, antioxidants and mixturesof these.

The additives described above may be present in the flame retardantpolymer compositions of the invention in amounts and in forms known inthe art, including in the form of so-called nanomaterials where at leastone of the dimensions of the particles is in the range of 1 to 1000 nm.The flame retardant polymer compositions described herein are melt-mixedblends, wherein all of the polymeric components are well-dispersedwithin each other and all of the non-polymeric ingredients arewell-dispersed in and bound by the polymer matrix, such that the blendforms a unified whole. Any melt-mixing method may be used to combine thepolymeric components and non-polymeric ingredients of the presentinvention.

The polymeric components and non-polymeric ingredients of the flameretardant polymer compositions of the invention may be added to a meltmixer, such as, for example, a single or twin-screw extruder; a blender;a single or twin-screw kneader; or a Banbury mixer, eithersimultaneously through a single step addition, or in a stepwise fashion,and then melt-mixed. When adding the polymeric components andnon-polymeric ingredients in a stepwise fashion, part of the polymericcomponents and/or non-polymeric ingredients are first added andmelt-mixed with the remaining polymeric components and non-polymericingredients being subsequently added and further melt-mixed until awell-mixed composition is obtained. When long-length fillers such as forexample long glass fibers are used in the composition, pultrusion may beused to prepare a reinforced composition.

The components of the intumescent additive mixture may be combined bymixing in a blender, Banbury mixer, roll mill, or any method for mixingand dispersing chemical compounds known to those skilled in the art, solong as the method does not result in degradation of the components. Thecomponents of the intumescent additive mixture may also be blendedindividually with the flame retardant additive b1) and/or thethermoplastic vulcanizate by a method that does not degrade theingredients of the intumescent mixture, for example in a Banbury mixeror an extruder.

Also described herein are uses of a flame retardant composition (i.e. aflame retardant mixture) comprising i) b1) the at least one flameretardant comprising a phosphinate of the formula (I); and/or adiphosphinate of the formula (II); and/or polymers of (I) and/or (II) asdescribed herein, ii) phosphorous-containing amino composition b2), andiii) the zeolite b3) described herein for imparting flame retardance andlow smoke emission to a composition comprising a) the one or morethermoplastic resins as described herein or other polymers that may bethermoplastic resins, thermoplastic elastomers or elastomers, whereinthe flame retardant composition (i.e. b1) plus b2) plus b3)) is presentin the flame retardant polymer composition in an amount from at or about18 to at or about 50 weight percent, the weight percentage being basedon the total weight of the flame retardant polymer composition andwherein b1) is present in the flame retardant polymer composition in anamount from at least 15 weight percent, preferably from at or about 15to 25 weight percent based on the total weight of the flame retardantpolymer composition, and b2) is present in the flame retardant polymercomposition in an amount such that the amount of b2) is lower than theamount of b1), preferably in an amount from at or about 5 to at or about15 weight percent based on the total weight of the flame retardantpolymer composition. Preferably, b3) is present in the flame retardantpolymer composition in an amount of at least 2 weight percent, even morepreferably in an amount from at or about 2 to at or about 20 weightpercent, based on the total weight of the flame retardant polymercomposition.

Also described herein are methods for imparting flame retardance and lowsmoke emission to an article made of a flame retardant polymercomposition, the method comprising melt blending a) the one or morethermoplastic vulcanizates described herein with b) a flame retardantcomposition comprising b1) the at least one flame retardant comprising aphosphinate of the formula (I); and/or diphosphinate of the formula(II); and/or polymers of (I) and/or (II) as described herein, b2) thephosphorous-containing amino composition selected from the groupconsisting of melamine phosphates, derivatives of melamine phosphatesand mixtures thereof; and b3) the zeolite described herein, wherein theflame retardant composition is present in an amount from at or about 18to at or about 50 weight percent (the weight percentage being based onthe total weight of the flame retardant polymer composition), b1) ispresent in the b) flame retardant composition in an amount from at orabout 30 to at or about 85 weight percent, b2) is present in the b)flame retardant composition in an amount greater than 10 to at or about30 weight percent, and b3) is present in the b) flame retardantcomposition in an amount from at or about 4 to at or about 40 weightpercent, provided that the sum b1) b2) b3) is 100%, so as to form aflame retardant polymer composition and shaping said flame retardantpolymer composition.

Also described herein are methods for imparting flame retardance and lowsmoke emission to an article made of a flame retardant polymercomposition, the method comprising melt blending the intumescentadditive composition described herein, the component b1) component andthe one or more thermoplastic vulcanizates described herein.

The flame retardant polymer compositions described herein may be shapedinto articles using methods known to those skilled in the art, such asinjection molding, blow molding, injection blow molding, extrusion,thermoforming, melt casting, vacuum molding, rotational molding,calendar molding, slush molding, filament extrusion and fiber spinning.Such articles may include films, fibers and filaments, wire and cablecoatings; photovoltaic cable coatings, optical fiber coatings, tubingand pipes; fabrics or texiles made from fibers and filaments, e.g., usedin clothing or carpets; films and membranes such breathable membranes inroofing and building/construction; motorized vehicle parts such as bodypanels, air bag doors, dashboards, engine covers, rocker panels or airfilter covers; components for household appliances, such as washers,dryers, refrigerators and heating-ventilation-air conditioningappliances; connectors in electrical/electronic applications; componentsfor electronic devices, such as computers; components for office-,indoor-, and outdoor-furniture; and footwear components.

EXAMPLES

The invention is further illustrated by certain embodiments in theExamples below which provide greater detail for the compositions, usesand processes described herein.

The following materials were used to prepare the flame retardant polymercompositions described herein and the compositions of the comparativeexamples.

Thermoplastic vulcanizate: a copolyetherester vulcanizate containingabout 50.2 weight percent of a copolyetherester elastomer, the weightpercentage being based on the total weight of the copolyetherestervulcanizate. The copolyetherester elastomer contained about 15.8 weightpercent of poly(tetramethylene oxide) having an average molecular weightof about 1000 g/mol as polyether block segments, the weight percentagebeing based on the total weight of the copolyetherester elastomer. Theshort chain ester units were polybutylene terephthalate segments.

The crosslinked rubber dispersed phase of the thermoplastic vulcanizateswas an ethylene methyl acrylate copolymer comprising 62 weight percentof copolymerized methyl acrylate units, the weight percentage beingbased on the total weight of the copolymer. The remainder of thecomonomer units were copolymerized ethylene units. The rubber wascrosslinked using about 3.4 weight percent of2,5-dimethyl-2,5-di-(t-butylperoxy)hexyne-3 (DYBP) as peroxide curativeand about 4.6 weight percent of the organic multiolefinic co-agentdiethylene glycol dimethacrylate (DEGDM), the weight percentage beingbased on the total weight of the ethylene methyl acrylate copolymerrubber. The thermoplastic vulcanizate comprised about 2 weight percentof suitable heat stabilizers and/or antioxidants includingdiphenylamines, amides, thioesters, phenolic antioxidants and/orphosphites. The copolyetherester vulcanizate was prepared according tothe process described herein in the detailed description of theinvention and in Int'l. Patent Appln. Publn. No. WO 20041029155.

Phosphinate flame retardant: Exolit® OP935, an aluminum salt of diethylphosphinate having a D90 max of 7.506 microns supplied by Clariant.Melamine pyrophosphate (MPP): MelBan 13-1100 supplied by Hummel Croton,Inc., South Plainfield, N.J., USA.Coated melamine pyophosphate: a melamine pyrophosphate coated with0.6±0.1 wt.% Silquest® A-1100 silane.Ammonium polyphosphate: Budit® 3168 supplied by Budenheim, GermanyZeolite: Zeolyst™ CBV100 supplied by Zeolyst International,Conshohocken, Pa., USA. This product is a Y type zeolite (NaY) of a FAUframework type having the following characteristics:SiO₂Al2O3 mole ratio: 5.1;nominal cation form: sodium;Na₂O weight percent: 13.0;unit cell size: 24.65 A:surface area: 900 m2/g.

For each composition of an Example or composition of a ComparativeExample, the materials in the amount listed in Tables 1-7 were meltblended in a 30 mm twin screw extruder (Coperion ZSK 30) operated at abarrel temperature of about 220° C. to 240′C using a screw speed ofabout 150 rpm to 250 rpm and a throughput of about 6 to about 12kg/hour. The compounded melt blended mixtures were extruded in the formof narrow strips (or bands) having an average thickness as indicated inthe Tables. Quantities shown in the Tables are presented in weightpercent on the basis of the total weight of the composition.

In the Tables, compositions of the Examples are identified as “E” andcompositions of the Comparative Examples are identified as “C”. Table 1provides a list of components corresponding to composition E1 andcompositions C0-C2. Similarly, Tables 2-7 provide a list of componentscorresponding to compositions E2-E31 and C3-C27.

The following test methods were used to determine physical properties,

Flame Retardance

Flammability testing was performed according to UL 94 test standard, 20mm vertical burning test. Test specimens were prepared from thecompositions of the tables by melt-extruding narrow flat strips in astandard extruder having barrel temperatures set at about 220° C. toabout 240° C. Test specimens, in the shape of rectangular bars ofdimension 125 mm long by 13 mm wide, were cut from the thus-obtainedflat strips.

Test specimens were clamped with the longitudinal axis vertical toposition the lower edge of the specimen was 300 mm above a horizontallayer of dry absorbent surgical cotton. A burner producing a blue flame20 mm high was placed so that the flame was applied centrally to themid-point of the lower edge of the specimen for 10 seconds. After theapplication of the flame to the specimen for 10 seconds, the burner waswithdrawn from the sample and the after-flame time, t₁, was measured.When after-flaming of the test specimen stopped, the burner was replacedbeneath the specimen for an additional 10 seconds. The flame was thenwithdrawn from the sample and the second after-flame time, t₂, wasmeasured. Materials were classified according to the test specificationsas V-0, V-1 or V-2, based on the behavior of the composition duringburning. When the composition failed to meet the criteria for the leastdemanding classification (V-2), it is reported as “failed” in thetables.

Flammability was measured for all compositions after they had beenpreconditioned for at least 48 hours at 23° C. and 50 percent relativehumidity.

Smoke Emission Method

Equipment and Set-Up Method

The equipment included a heat source which was a laboratory burneraccording to UL 94 standard “Tests for Flammability of Plastic Materialsfor Parts in Devices and Appliances”. Gas supply—a supply of technicalgrade methane gas with regulator and meter for uniform gas flow.

The sample holder was a porcelain crucible which was inert to thematerial being tested. The crucible had a height of 36 mm and anexternal diameter of 45 mm (model VWR 102/45 DIN). The crucible wasplaced within a triangular porcelain holder having a height of 47 mm andsides of 56 mm. The triangular holder was attached via wire means onto athree-legged support having a height of 220 mm, an external diameter of170 mm and a wall thickness of round section of 15 mm. The height of thecrucible with respect to the laboratory burner was adjusted so that thetop of the flame touched and was centrally positioned to touch thebottom of the crucible. A round piece of aluminum foil of externaldiameter 120 mm having a center circular hole of 44 mm diameter andsufficient to fit the crucible was placed atop the triangular holder.

A glass chimney having a total height of 300 mm, a bottom insidediameter of 100 mm, a height of cylinder before striction of 270 mm, anda top inside diameter of 50 mm was placed atop and in direct contactwith the aluminum foil. A plastic cone having holes was fitted into thetop section of the glass chimney; the cone having a bottom insidediameter of 46 mm, a top inside diameter of 32 mm, a height of 94 mm anda height remaining above the top surface of the chimney of 68 mm; thecone had 22 open holes of diameter 5 mm. A metal plate was placed atopthe upper surface of the plastic cone; the metal plate having dimensionssuch that it was at least as large as the upper surface of the plasticcone. The glass chimney was supported in place by means of at least onepoint fixed to a vertical metal stand.

A photometric system of the following type was also used—Light Source:Model Makita ML700 flashlight; Lens diameter 21 mm; Power 7.2V, capacity1.3Ah. Receiver—Photocell: Glass-EVA-cell-EVA-glass laminated system.The EVA was a Vistasolar® film type 486.10 from ETIMEX Solar GmbH(Dietenheim, Germany); the cell was a polycrystalline silicone cell fromQ-cells AG type Q6LTT-18011410 having an edge length of 156 mm and anefficiency of >=14.1%. Standard lamination conditions at 140° C. for 18minutes were followed. The photocell was Kapton® taped at the edges andhad a final dimension of 200 m×200 mm.

For data collection, an Oscilloscope Model LeCroy 9304 Quad 175 MHz wasused. The light source and the receiver were placed on the left andright side respectively of the glass chimney and in the center of thechimney walls. The distance between the light source and the outer leftsurface of the chimney was 160 mm and the distance between the outerright surface of the chimney and the receiver was 360 mm. The receiverwas connected to the oscilloscope and the signal output in volts wasrecorded.

All equipment except the oscilloscope was placed inside a laboratoryfume hood according to UL 94 standard “Tests for Flammability of PlasticMaterials for Parts in Devices and Appliances”. The fume hood used wasfrom Atlas Fire Science Products, Plastics HVUL. To preventconcentration of fumes inside the hood a light aspiration was maintainedin the fume hood. A protection shield was placed around the laboratoryburner to prevent any instability in the flame. After completion of eachmeasurement the fume hood ventilation system was opened to permitcomplete exhaust of the fumes.

Example 1 and Comparative Examples C0-C2

TABLE 1 C0 C1 C2 E1 Thermoplastic vulcanizate 85 75 75 75 Phosphinateflame retardant 15 15 15 15 Zeolite — 10 0.5 2 Coated melaminepyrophosphate — — 9.5 8 Flammability testing V-2 V-2 Failed V-0 (t1 +t2)avg 9 15 42 8 (It, sample/Io, sample) 0.21 0.36 0.61 0.79

Table 1 shows that the composition C0, comprising only a phosphinateflame retardant, exhibited flame retardance but minimum lighttransmission, i.e., “0.21”, indicating relatively high smoke emission.The composition C1 contained the same amount of flame retardant as C0and contained zeolite. C1 exhibited improved smoke emission relative toC0.

The Example E1 composition exhibits increased flame retardantperformance relative to C0, C1 and C2 as indicated by the V-0 rating forE1 vs. the V-2 and failed ratings for the comparative samples. Inaddition, E1 exhibits improved smoke emission relative to thecomparative samples as indicated by the value for lt/lo of 0.79 for E1vs. lt/lo values of 0.21 for C0, 0.36 for C1 and 0.61 for C2.

Examples E2-E5 and Comparative Examples C3-C9

A series of compositions was prepared having components as shown inTable 2. The thermoplastic vulcanizate composition, flame retardant,melamine pyrophosphate and zeolite were the same as those used in thecompositions shown in Table 1. Smoke evaluation was conducted for eachcomposition and a reference sample. The reference sample andcompositions were tested on the same day under the same conditions. Thereference sample in Table 2 is C9.

The data in Table 2 indicate that improved smoke emission and anacceptable flammability (V-1 or V-2) is exhibited by compositions thatcontain an amount of phosphinate b1) higher than the amount ofphosphorous-containing amino composition b2).

Comparative Examples C10-C19

A series of compositions was prepared having components as shown inTable 3. The thermoplastic vulcanizate composition, flame retardant,melamine pyrophosphate and zeolite were the same as those used in thecompositions shown in Table 1. Smoke evaluation was conducted for eachcomposition and a reference sample. The reference sample andcompositions were tested on the same day under the same conditions. Thereference sample in Table 3 is C9.

Comparative Examples C20-23

A series of compositions was prepared having components as shown inTable 4. The thermoplastic vulcanizate composition, the phosphinateflame retardant and zeolite were the same as those used in thecompositions shown in Table 1. Smoke evaluation was conducted for eachcomposition and a reference sample. The reference sample andcompositions were tested on the same day under the same conditions. Thedata shown in table 4 indicate that when zeolite is used in combinationwith phosphinate, but in the absence of a phosphorous-containing aminocompound, flammability of the polymer composition is improved but thereis only a modest effect on smoke emission.

Examples E6-E15 and Comparative Example C20

A series of compositions was prepared having components as shown inTable 5. The thermoplastic vulcanizate composition, flame retardant,melamine pyrophosphate and zeolite were the same as those used in thecompositions shown in Table 1. Smoke evaluation was conducted for eachcomposition and a reference sample. All Example compositions exhibitedacceptable flammability ratings (V-0, V-1 or V-2). The reference sampleand compositions were tested on the same day under the same conditions.The reference sample in Table 5 is E12. The data in Table 5 indicatethat the compositions of E6 to E15 show an improved smoke emission and agood flammability compared to C20, which contains no zeolite.

Examples E16-E24 and Comparative Example C24

A series of compositions was prepared having components as shown inTable 6. The thermoplastic vulcanizate composition, flame retardant andzeolite were the same as those used in the compositions shown inTable 1. The melamine pyrophosphate was an uncoated melaminepyrophosphate. Smoke evaluation was conducted for each composition and areference sample. The reference sample and compositions were tested onthe same day under the same conditions. The reference sample in Table 6is E12 of table 5.

Examples E25-E31 and Comparative Examples C25-C27

A series of compositions was prepared having components as shown inTable 7. The thermoplastic vulcanizate composition, flame retardant andzeolite were the same as those used in the compositions shown inTable 1. Ammonium polyphosphate was used as b2), the phosphorousamino-containing compound. Smoke evaluation was undertaken for eachcomposition and a reference sample. The reference sample andcompositions were tested on the same day under the same conditions. Thereference sample in Table 7 is E12 of table 5.

TABLE 2 E2 C3 C4 C5 E3 C6 E4 C7 C8 E5 C9 Thermoplastic 75 75 75 75 75 7575 75 75 75 85 vulcanizate Phosphinate flame 15 11.5 9.9 8 15 12.45 158.95 11.98 15 15 retardant Zeolite 2 2 0.1 2 1.05 0.1 0.1 1.05 1.05 0.5— Coated Melamine 8 11.5 15 15 8.95 12.45 9.9 15 11.98 9.5 —pyrophosphate Flammability testing V-1 Failed Failed V-2 V-1 Failed V-1V-2 Failed V-1 V-2 (t1 + t2) avg 22.4 38.8 31.8 25.8 25.0 35.0 27.8 27.450.0 25.2 10 Band thickness avg 1.9 1.9 1.9 1.9 1.9 1.9 1.9 1.9 1.8 1.91.9 (mm) (It, sample/Io, 0.70 0.69 0.30 0.22 0.73 0.38 0.66 0.22 0.570.62 0.4 sample) (It, ref/Io, ref) 0.35 0.35 0.35 0.35 0.41 0.41 0.410.41 0.41 0.41 —

TABLE 3 C10 C11 C12 C13 C14 C15 C16 C17 C18 C19 C9 Thermoplastic 80 8080 80 80 80 80 80 80 80 85 vulcanizate Phosphinate flame 12 9.2 7.9 6.412 9.96 12 7.16 9.58 12 15 retardant Zeolite 1.6 1.6 0.1 1.6 0.84 0.080.08 0.84 0.84 0.4 — Coated Melamine 6.4 9.2 12 12 7.16 9.96 7.92 12.09.58 7.6 — pyrophosphate Flammability testing Failed Failed V-2 V-2Failed Failed Failed V-2 Failed V-2 V-2 (t1 + t2) avg 38.4 48.8 20.622.4 37.8 31.8 52 23.6 31.6 28.2 10 Band thickness avg 1.9 1.8 1.9 1.91.9 2.0 2.0 1.9 1.9 1.9 1.9 (mm) (It, sample/Io, 0.67 0.54 0.20 0.240.58 0.57 0.55 0.16 0.39 0.52 0.25 sample) (It, ref/Io, ref) 0.24 0.240.24 0.24 0.24 0.24 0.27 0.27 0.27 0.27 —

TABLE 4 C20 C21 C22 C23 Thermoplastic 85 83 80 75 vulcanizatePhosphinate flame 15 15 15 15 retardant Zeolite — 2 5 10 Melamine — — —— pyrophosphate Flammability testing V-2 V-0 V-0 V-0 (t1 + t2)avg 7.76.8 9.2 8.6 Band thickness avg 1.8 1.8 1.8 1.8 (mm) (It, sample/Io, 0.140.11 0.1 0.22 sample) (It, ref/Io, ref) 0.62 0.62 0.62 0.62

TABLE 5 E6 E7 E8 E9 E10 E11 E12 E13 E14 E15 C20 Thermoplastic 81 78 7378 75 70 75 72 67 75 85 vulcanizate Phosphinate flame 15 15 15 15 15 1515 15 15 15 15 retardant Zeolite 2 5 10 2 5 10 2 5 10 1 — CoatedMelamine 2 2 2 5 5 5 8 8 8 9 — pyrophosphate Flammability testing V-0V-1 V-1 V-1 V-0 V-1 V-0 V-0 V-0 V-1 V-2 (t1 + t2) avg 8.6 13.6 27.2 14.87.8 24.7 6 5.7 4.7 18.7 7.7 Band thickness avg 1.8 1.8 1.8 1.8 1.8 1.81.8 1.8 2.0 2.1 1.8 (mm) (It, sample/Io, 0.33 0.39 0.74 0.76 0.83 0.860.60 0.75 0.80 0.57 0.14 sample) (It, ref/Io, ref) 0.60 0.60 0.60 0.600.60 0.60 0.60 0.82 0.82 0.62 0.62

TABLE 6 C24 E16 E17 E18 E19 E20 E21 E22 E23 E24 Thermoplastic 81 78 7378 75 70 75 72 67 75 vulcanizate Phosphinate flame 15 15 15 15 15 15 1515 15 15 retardant Zeolite 2 5 10 2 5 10 2 5 10 1 Uncoated melamine 2 22 5 5 5 8 8 8 9 pyrophosphate Flammability testing Failed V-1 V-1 V-1V-0 V-0 V-0 V-0 V-0 V-0 (t1 + t2) avg 47.3 22.7 17 11.3 8.3 9.0 5.7 3.37.0 7.0 Band thickness avg 1.9 2.0 2.0 2.0 2.0 2.0 1.8 1.8 1.8 2.0 (mm)(It, sample/Io, 0.39 0.36 0.22 0.74 0.77 0.71 0.76 0.77 0.82 0.58sample) (It, ref/Io, ref) 0.76 0.76 0.76 0.76 0.76 0.76 0.76 0.76 0.760.74

TABLE 7 E25 E26 E27 E28 E29 E30 C25 C26 E31 C27 Thermoplastic 81 78 7378 75 70 75 72 67 75 vulcanizate Phosphinate flame 15 15 15 15 15 15 1515 15 15 retardant Zeolite 2 5 10 2 5 10 2 5 10 — Budit ® 3168 2 2 2 5 55 8 8 8 10 Flammability testing V-0 V-1 V-1 V-1 V-2 V-0 Failed FailedV-2 Failed (t1 + t2) avg 8 14 19.3 40.7 17.3 7.0 44 29.7 33.3 32.3 Bandthickness avg 2.0 1.8 1.8 1.8 1.7 1.7 1.8 1.7 1.6 1.7 (mm) (It,sample/Io, 0.37 0.55 0.40 0.26 0.58 0.74 0.38 0.57 0.53 0.63 sample)(It, ref/Io, ref) 0.74 0.74 0.74 0.74 0.74 0.74 0.74 0.74 0.74 0.62

1. A flame retardant polymer composition comprising: a) one or more thermoplastic vulcanizates; and b) from at or about 18 to at or about 50 weight percent, based on the total weight of the flame retardant polymer composition of a flame retardant mixture comprising: b1) at least one flame retardant comprising a material selected from the group consisting of phosphinates of the formula (I); diphosphinates of the formula (II); polymers of (I); polymers of (II); and mixtures of two or more thereof

wherein R₁ and R₂ are independently selected from hydrogen, linear or branched C₁-C₆ alkyl groups, and aryl groups; R₃ is a linear or branched C₁-C₁₀-alkylene group, a C₆-C₁₀ arylene group, an alkylarylene group or an arylalkylene group; M is selected from the group consisting of calcium, magnesium, aluminum, zinc and mixtures thereof; m is 2 to 3; n is 1 or 3; and x is 1 or 2; b2) a phosphorous-containing amino composition selected from the group consisting of melamine phosphates, derivatives of melamine phosphates and mixtures thereof, reaction products of ammonia with phosphoric acid, polyphosphates of said reaction products, and mixtures thereof; and b3) a zeolite, wherein; b1) is present in the flame retardant polymer composition in an amount greater than or equal to 15 weight percent based on the total weight of the flame retardant polymer composition, ii) b2) is present in the flame retardant mixture b) in an amount such that the amount of b2) is less than the amount of b1), and iii) b1) is present in the flame retardant mixture b) in an amount from at or about 30 to at or about 85 weight percent, b2) is present in the flame retardant mixture b) in an amount greater than 10 to at or about 30 weight percent, and b3) is present in the flame retardant mixture b) in an amount from at or about 4 to at or about 40 weight percent, provided that the sum b1) b2) b3) is 100 weight percent.
 2. A flame retardant polymer composition according to claim 1, wherein each of the one or more thermoplastic vulcanizates is a composition comprising: (i) from about 15 to about 75 weight percent of at least one thermoplastic polyester continuous phase; and (ii) from about 25 to about 85 weight percent of at least one poly(meth)acrylate or polyethylene/(meth)acrylate rubber that forms a dispersed phase, wherein the rubber is dynamically crosslinked with at least one peroxide free radical initiator and at least one organic multiolefinic co-agent; the weight percentages being based on the total weight of (i) plus (ii).
 3. A flame retardant polymer composition according to claim 2 wherein the thermoplastic polyester continuous phase (i) comprises at least one elastomer selected from the group consisting of copolyester elastomers, copolyetherester elastomers and mixtures thereof.
 4. A flame retardant polymer composition according to claim 2 wherein the thermoplastic polyester continuous phase (i) comprises at least one copolyester elastomer or copolyetherester elastomer that is a copolymer having a multiplicity of recurring long-chain ester units and short-chain ester units joined head-to-tail through ester linkages, said long-chain ester units being represented by formula (A):

and said short-chain ester units being represented by formula (B):

wherein: G is a divalent radical remaining after the removal of terminal hydroxyl groups from poly(alkylene oxide)glycols having a number average molecular weight of between about 400 and about 6000; R is a divalent radical remaining after removal of carboxyl groups from a dicarboxylic acid having a molecular weight of less than about 300; and D is a divalent radical remaining after removal of hydroxyl groups from a diol having a molecular weight less than about
 250. 5. A flame retardant polymer composition according to claim 4, wherein the thermoplastic polyester is a copolyetherester elastomer prepared from monomers comprising (1) poly(tetramethylene oxide) glycol; (2) a dicarboxylic acid selected from the group consisting of isophthalic acid, terephthalic acid and mixtures thereof; and (3) a diol selected from the group consisting of 1,4-butanediol, 1,3-propanediol and mixtures thereof.
 6. A flame retardant polymer composition according to claim 4, wherein the copolyetherester elastomer is prepared from monomers comprising (1) poly(trimethylene oxide) glycol; (2) a dicarboxylic acid selected from the group consisting of isophthalic acid, terephthalic acid and mixtures thereof; and (3) a diol selected from the group consisting of 1,4-butanediol, 1,3-propanediol and mixtures thereof.
 7. A flame retardant polymer composition according to claim 4, wherein the copolyetherester elastomer is prepared from monomers comprising (1) ethylene oxide-capped polypropylene oxide) glycol; (2) dicarboxylic acids selected from the group consisting of isophthalic acid, terephthalic acid and mixtures thereof; and (3) a diol selected from the group consisting of 1,4-butanediol, 1,3-propanediol, and mixtures thereof.
 8. A flame retardant polymer composition according to claim 1 wherein the at least one flame retardant b1) is selected from the group consisting of aluminum phosphinate, aluminum diethyl phosphinate and zinc diethyl phosphinate.
 9. A flame retardant polymer composition according to claim 1 wherein the zeolite b3) is represented by the general formula M_(2/n)O.Al₂O₃ .xSiO₂ .yH₂O wherein M is a metal selected from alkali and alkaline earth metals, V, Mo, Mn, Fe, Co, Ni, Cu, Zn, Sb, Bi and mixtures thereof; n is the cation valence; x is from 0.1 to 20; and y is the number of moles of water of crystallization and has a value of 0 to
 20. 10. A flame retardant polymer composition according to claim 1 wherein the phosphorous-containing amino composition comprises melamine pyrophosphate.
 11. A flame retardant polymer composition according to claim 10 wherein the amount of melamine pyrophosphate is greater than 2 weight percent based on the total weight of the flame retardant polymer composition.
 12. A flame retardant polymer composition according to claim 1 wherein b3) is present in the flame retardant polymer composition in an amount from at or about 20 weight percent based on the total weight of the flame retardant polymer composition.
 13. A flame retardant polymer composition according to claim 1 wherein the flame retardant mixture b) comprises i) b1) which is present in the flame retardant polymer composition in an amount from at or about 15 to 25 weight percent based on the total weight of the flame retardant polymer composition, ii) b2) which is present in the flame retardant polymer composition in an amount from at or about 5 to 15 weight percent based on the total weight of the flame retardant polymer composition and iii) b3) which is present in the flame retardant polymer composition in an amount from at or about 2 to 20 weight percent based on the total weight of the flame retardant polymer composition.
 14. A molded, extruded, or shaped article comprising the flame retardant polymer composition recited in claim
 1. 15. A wire or cable comprising a coating made of the flame retardant polymer composition recited in claim
 1. 16. An optical cable comprising a coating made of the flame retardant polymer composition recited in claim
 1. 17. A process for imparting flame retardance and low smoke emission to a composition comprising one or more thermoplastic vulcanizates, the process comprising the step of mixing A. a flame retardant composition comprising 1) at least one flame retardant comprising a material selected from the group consisting of phosphinates of the formula (I); diphosphinates of the formula (II); polymers of (I); polymers of (II); and mixtures of two or more thereof;

wherein R₁ and R₂ are independently selected from hydrogen, linear or branched C₁-C₆ alkyl groups, aryl groups and mixtures thereof; R₃ is a linear or branched C₁-C₁₀ alkylene group, a C₆-C₁₀arylene group, an alkylarylene group or an arylalkylene group; M is selected from the group consisting of calcium, magnesium, aluminum; zinc and mixtures thereof; m is 2 to 3; n is 1 or 3; and x is 1 or 2; 2) a phosphorous-containing amino composition selected from the group consisting of reaction products of ammonia with phosphoric acid, polyphosphates of said reaction products, and mixtures thereof; and 3) a zeolite wherein the flame retardant of 1) is present in the flame retardant composition in an amount from at or about 30 to at or about 85 weight percent, ii) the phosphorous-containing amino composition of 2) is present in the flame retardant composition in an amount greater than 10 to at or about 30 weight percent, and iii) the zeloite is present in the flame retardant composition in an amount from at or about 4 to at or about 40 weight percent, provided that the sum 1)+2)+3) is 100 weight percent; and B. one or more thermoplastic vulcanizates. 